Cross-Coupling Hydrogen Evolution by Visible Light Photocatalysis Toward C(sp2)-P Formation: Metal-Free C-H Functionalization of Thiazole Derivatives with Diarylphosphine Oxides

Visible light along with 5 mol % eosin B catalyzed the first direct C-H phosphorylation of thiazole derivatives with diarylphosphine oxides by a photoredox process in the absence of an external oxidant. The scope of thiazoles and phosphine oxides was further investigated, as was functional group tolerance. The general and operational simplicity provides a novel metal and oxidant-free alternative for the formation of heteroaryl-P bonds, and only molecular hydrogen is generated as a byproduct.